#include<stdio.h>

void swap(int* pa, int* pb){
	int temp = *pa;
	*pa = *pb;
	*pb = temp;
	return;
}

int main()
{
	int x = 10;
	int y = 20;
	swap(&x,&y);
	printf("x=%d, y=%d\n", x, y);

	return 0;
}
